GRUESOME VIOLENCE: These grabs from an IS propaganda video allegedly show 25 Syrian government soldiers on their knees in the ancient amphitheatre in Palmyra awaiting their execution. It appears the soldiers were executed by children or teenagers.AFP

Child terrorists in kill video

THE Islamic State group has released a video showing the killing of 25 government soldiers in the historic town of Palmyra in central Syria.

The nearly 10-minute long video showed the soldiers being taken in trucks from Palmyra's notorious Tadmur prison to the town's ancient Roman amphitheatre.

The video shows the soldiers in green and brown military uniforms being shot dead on the amphi

theatre's stage in front of the group's black-and-white flag.

The executioners all appear to be children as young as 10 and are wearing desert camouflage and brown bandanas.

The killings are carried out in front of a relatively sparse crowd of men and some children watching from the ancient theatre's seats.

Hundreds were seen watching the killings which may have taken place inside the Palmyra amphitheatre on May 27, according to the Syrian Observatory for Human Rights, a Britain-based monitoring group that first reported the event.

It was not clear if these were the executions in the video.

The terrorists reportedly killed more than 200, including civilians, during their takeover of the city. Just days after the takeover, IS murdered 20 men in the amphitheatre.

Palmyra is a UNESCO World Heritage site famous for its 2000-year-old Roman colonnades, other ruins and priceless artefacts.

IS has desecrated two Muslim graves and used sledgehammers to destroy statues outside the Palmyra Museum, the Agence France-Presse reported.

At the time, Syria's antiquities director Mamoun Abdelkarim said he feared the killings could signal the start of "the group's barbarism and savagery against the ancient monuments of Palmyra".

"Using the Roman theatre to execute people proves that these people are against humanity," he said.

IS has regularly released videos of its mass executions, with slick production and gruesome violence that experts say is a key propaganda tool for the group.

It was estimated recently IS had been responsible for the deaths of 3027 civilians, rebels and soldiers since the declaration of its alleged "caliphate".

The terror group executed 1787 civilians, including 74 children and 86 women, by shooting, beheading, stoning, throwing from high places and burning.

IS was said to be funding its military expansion by establishing a monopoly on selling artefacts looted from ancient cities, while punishing lone smugglers who tried to sell outside the system.